Description (from application): The Scid Mouse: Skin xenograft core utilizes severe combined immunodeficient mice to provide reproducible sustenance of human skin (and skin-related cells) in the form of split thickness skin grafts. The three specific aims of the core are ( 1 ) to provide members of the YSDRC (both established and junior investigators, including investigators with YSDRC P/F projects) with limited numbers of C.B.-17 SCID/beige mice engrafted with healthy adult human skin for use in a variety of skin disease-related studies, including feasibility studies; (2) to train members of the YSDRC in generation of such mice once feasibility has been established; and (3) to develop variant models of this technique for new and novel applications.